Search PubMed⌕ Search

Biomedical subjects

S Greenfield

Publications and source records attributed to S Greenfield.

At least 55 records · Page 3Linked to original sources
PubMed1997

Enuresis and common voiding abnormalities.

Voiding problems, and in particular nocturnal enuresis, can usually be evaluated and managed without resorting to complex procedures or invasive tests. A good history with attention to toilet habits and the possible presence of infection can help distinguish patients who may have significant organic pathologic conditions who require further investigation. Wetting alarms are effective with a low recidivism rate but are noisy. DDAVP is effective, works rapidly, and is discrete but has a higher recidivism rate. Treatment is aimed at correcting any poor toilet habits and using the appropriate alarm device or medication.

Behavior Therapy↗
PubMed1996

Characteristics of physicians with participatory decision-making styles.

OBJECTIVES: To identify physician and practice characteristics associated with a physician's propensity to involve patients in diagnostic and treatment decisions, or participatory decision-making style. DESIGN: A representative cross-sectional sample of patients participating in the Medical Outcomes Study characterized each physician's style by using a self-reported questionnaire. A single averaged style score was generated for each physician. Style scores were compared among physicians who differed in age, sex, minority status, specialty, primary care training or training in interviewing skills, satisfaction with professional autonomy, and practice volume. SETTINGS: Solo practices, multispecialty groups, and health maintenance organizations in Boston, Chicago, and Los Angeles. PARTICIPANTS: 7730 patients sampled over 9 days from the practices of 300 physicians. Physicians were practicing general internal medicine, family medicine, cardiology, and endocrinology. MEASUREMENTS: Participatory decision-making style was measured using a three-item scale on a questionnaire that was completed by patients after their office visit. Physician and practice characteristics were reported by physicians on self-administered questionnaires. RESULTS: Among patients of physicians who were rated in the lowest (least participatory) quartile, one third changed physicians in the following year; among patients of physicians who were rated in the highest quartile, only 15% changed physicians. Higher scores were associated with greater patient satisfaction. Physicians who had had primary care training or training in interviewing skills scored higher than those without such training. Physicians in higher-volume practices were rated as less participatory than those in lower-volume practices. Physicians who were satisfied with their level of professional autonomy were rates as more participatory than those who were dissatisfied. CONCLUSION: Participatory decision-making style is influenced by physicians' background, training, practice volume, and professional autonomy. Because participatory decision-making style is related to patient satisfaction and loyalty to the physician, cost-containment strategies that reduce time with patients and decrease physician autonomy may result in suboptimal patient outcomes.

Cross-Sectional Studies↗
PubMed1996

Forum Three: Changes in the U.S. health care system that would facilitate improved care for non-insulin-dependent diabetes mellitus.

At the conclusion of the conference detailed in this supplement, conference attendees participated in one of three fora to discuss an assigned topic and incorporate conference presentations into the discussion. Forum Three, the results of which are reported here, addressed the challenging question of what changes in the U.S. health care system would facilitate improved care for patients with non-insulin-dependent diabetes mellitus (NIDDM). Using the nominal group process-a discussion technique designed to obtain a rank-ordered list of responses to the challenge question from a group of informed persons-Forum Three made the following priority recommendations: 1) Establish universal access to the comprehensive preventive services necessary to optimally manage the estimated 16 million Americans with NIDDM; 2) create a system of co-management between primary and specialty care services; and 3) modify the current health care system to include a program for increased patient and public awareness of the seriousness of NIDDM, special training for primary care residents and practicing physicians in this area, development of standards of care, creation of a central coordinating agency for all aspects of diabetes care, and development of outcome-based goals for patients and providers.

Databases, Factual↗
PubMed1996

Computation of vascular flow dynamics from intravascular ultrasound images.

Analysis of three-dimensional velocity profiles and wall shear stress distribution in a segment of an artery reconstructed from in vivo imaging data are presented in this study. Cross-sectional images of a segment of the abdominal aorta in dogs were obtained using intravascular ultrasound (IVUS) imaging employing a constant pull back technique. Simultaneous measurement of pressures distal and proximal to the vessel segment along with gated pulsed Doppler velocity measurements were also obtained. The three-dimensional geometry of the vascular segment was reconstructed from the IVUS images during peak forward flow phase, and a computational mesh was constructed from the data. A quasi-steady analysis of incompressible Newtonian fluid was performed with a finite difference general purpose computational analysis program FLOW3D. The velocity at the inlet and pressure at the outlet measured at the corresponding time (time referenced to ECG) were used to specify the boundary conditions for the computational flow model. The computed results compared favorably with previously reported results. The purpose of the present study was to analyze the hemodynamics in vascular segments from morphologically realistic three-dimensional reconstructions. The method can be potentially employed in analyzing the hemodynamics in the region of atherosclerotic plaques at various stages of development and the reactivity of the vessel in response to pharmacological and mechanical interventions.

Animals↗
PubMed1996

Expanded followup of intravesical oxybutynin chloride use in children with neurogenic bladder.

PURPOSE: We evaluated the long-term results of intravesical oxybutynin chloride use in children with neurogenic bladders who could not tolerate or whose conditions were refractory to oral therapy. MATERIALS AND METHODS: We reviewed our experience with 28 children (myelomeningocele in 27 and imperforate anus in 1) who presented with urinary incontinence and/or elevated bladder pressures refractory to intermittent catheterization and oral anticholinergic medication. Intravesical oxybutynin was administered to each child by instillation of 5 mg. crushed oxybutynin chloride in 10 cc sterile saline 2 times daily during catheterization. RESULTS: Seven patients (25%) could not tolerate intravesical oxybutynin secondary to anticholinergic side effects. The remaining 21 children have been followed on intravesical oxybutynin for a mean of 35 months (range 3 to 67). Of these 21 children 12 (57%) became completely dry day and night, 5 (24%) achieved daytime continence between catheterizations and 4 (19%) remained clinically unchanged with 2 in diapers. On urodynamics these 21 patients had increased bladder capacity of up to 1,150% (mean 237%, p < 0.0001) and decreased mean maximum filling pressures of -31% (p = 0.002). CONCLUSIONS: Although a number of patients continued to have anticholinergic side effects, a majority had significant improvement in urodynamic parameters and continence. The response appears to be durable, and it spares many of these children from undergoing bladder augmentation.

Administration, Intravesical↗
PubMed1995

Outcomes of patients with hypertension and non-insulin dependent diabetes mellitus treated by different systems and specialties. Results from the medical outcomes study.

OBJECTIVE: To compare the outcomes of patients with hypertension and non-insulin-dependent diabetes mellitus (NIDDM) who were cared for in three different systems of care and by generalist and subspecialist physicians. DESIGN: An observational study with follow-up at three periods: (1) a 2-year study of 532 patients with hypertension and 170 patients with NIDDM who had entrance and exit histories, physical examinations, and laboratory tests; (2) a 4-year follow-up of 1044 patients with hypertension and 317 patients with NIDDM based on patient-reported functional status; and (3) 7-year mortality for 1296 patients with hypertension and 424 patients with NIDDM. SETTING AND PARTICIPANTS: Patients sampled from health maintenance organizations, large multispecialty groups, and solo or single-specialty group practices in Boston, Mass, Los Angeles, Calif, and Chicago, Ill. Patients were designated as belonging to one of three systems of care: fee for service; prepaid patients in solo or small single-specialty groups or in large multispecialty group practices, referred to as independent practice associations; and staff-model health maintenance organizations. The principal providers were family practitioners, general internists, cardiologists, or endocrinologists. MAIN OUTCOME MEASURES: Physiological, functional, and mortality. For hypertension, we measured blood pressure and stroke incidence. For NIDDM, we measured blood pressure, glycosylated hemoglobin level, visual function, vibration sense, ulcers and infections in the feet, and albumin excretion rate. Functional outcomes were assessed using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Mortality was assessed for the 7 years following the entrance examination. RESULTS: We found no evidence that any one system of care or physician specialty achieved consistently better 2-year or 4-year outcomes than others for patients with NIDDM or hypertension. Endocrinologists appeared to achieve better foot-ulcer and infection outcomes for patients with NIDDM, particularly when compared with family practitioners. However, no other specialist differences were found in any individual measures for either condition. Moreover, no adjusted mortality differences among systems or among physicians specialties were observed in the 7-year follow-up period. CONCLUSION: No meaningful differences were found in the mean health outcomes for patients with hypertension or NIDDM, whether they were treated by different care systems or by different physician specialists. Although prepaid medicine relies more heavily on generalist physicians than does fee for service, there is no evidence from these analyses that the quality of care of moderately ill patients with these two common disease was adversely affected. These findings must be viewed in light of the historically higher costs of fee-for-service medicine and of subspecialty physician practice.

Analysis of Variance↗
PubMed1995

Foot infections in diabetic patients. Decision and cost-effectiveness analyses.

OBJECTIVE: To examine the cost-effectiveness of approaches to the diagnosis and treatment of patients with type II (non-insulin-dependent) diabetes mellitus (NIDDM) who have foot infections and suspected osteomyelitis. DESIGN: Decision and cost-effectiveness analyses were performed using a Markov model. We examined the prevalence of osteomyelitis, the major complications and efficacies of long-term antibiotic therapy and surgery, and the performance characteristics of four diagnostic tests (roentgenography, technetium Tc 99m bone scanning, indium in 111-labeled white blood cell scanning, and magnetic resonance imaging). Data were drawn from the English-language literature using MEDLINE searches and bibliographies from selected articles. SETTING: Primary care. PATIENTS: Patients with NIDDM who had foot infections and suspected osteomyelitis but no signs of systemic toxicity. INTERVENTIONS: Following hospitalization for surgical débridement and intravenous antibiotic therapy: (1) treatment for presumed soft-tissue infection, (2) culture-guided empiric treatment for presumed osteomyelitis, (3) 71 combinations of diagnostic tests preceding antibiotic therapy for osteomyelitis, (4) 71 combinations of tests preceding amputation, and (5) immediate amputation. MAIN OUTCOME MEASURES: Quality-adjusted life expectancy, average costs. RESULTS: Culture-guided empiric treatment for osteomyelitis with 10 weeks of oral antibiotic therapy has similar effectiveness to testing followed by a long course of antibiotic therapy if any test result is positive. However, empiric treatment is the least expensive strategy. CONCLUSIONS: Noninvasive testing adds significant expense to the treatment of patients with NIDDM in whom pedal osteomyelitis is suspected, and such testing may result in little improvement in health outcomes. In patients without systemic toxicity, a 10-week course of culture-guided oral antibiotic therapy following surgical débridement may be as effective as and less costly than other approaches.

Amputation, Surgical↗
PubMed1995

Investigation of decomposition products of microwave digestion of food samples.

The involatile residues remaining after closed-vessel microwave digestion of various food samples, using nitric acid, with and without post-digestion treatment with hydrogen peroxide, have been studied. Decomposition products were found to include aliphatic and aromatic acids, nitro-compounds, oxalates and inorganic nitrates and phosphates. Measures of digestion completeness were provided by appearance, carbon content, infrared spectra and thin layer chromatograms of the residues, enabling a comparison of different digestion methods and sample types. Residual carbon levels varied linearly with the relative amounts of carboxylic acid and inorganic nitrate, as measured by infrared spectrometry of the residues. The formation of calcium oxalate was also a function of the degree of decomposition: the carboxylic acid: oxalate ratio increased in a logarithmic fashion with increasing residual carbon content. Particularly high levels of residual carbon from nitric acid digestion of milk powder, due largely to carboxylic acid residues, were substantially decreased by post-digestion treatment with hydrogen peroxide. However, nitrobenzoic acids, which proved major interferents in electrochemical analysis, were only removed by treatment with perchloric acid.

Food↗
PubMed1995

Comparing outcomes and charges for patients with acute myocardial infarction in three community hospitals: an approach for assessing "value".

OBJECTIVE: To assess the value of care (i.e. outcomes in relation to charges) for acute myocardial infarction (Acute MI) patients in three community hospitals after controlling for patient mix differences. DESIGN: An observational study of a cohort of acute MI patients admitted to hospital for care were studied based on medical record review and on patient-completed questionnaires at 8 weeks post-discharge. SETTING: Three community hospitals located in urban areas in the southeastern region of the United States. PATIENTS: A consecutive sample of 133 non-transfer Acute MI patients were entered into the study based on EKG results, enzyme tests and chest pain characteristics. Hospital medical record and charge data were available on all patients and patient-reports on 86% of survivors. MAIN OUTCOME MEASURES: Data were gathered on clinical outcomes (death, angina, dyspnea), functional outcomes (physical and psychosocial), satisfaction, and resource intensity (length of stay, total hospital charges, ancillary charges). Because of patient mix differences across hospitals, outcomes were adjusted for severity of Acute MI, comorbidity and demographics. RESULTS: There were important patient mix differences across hospitals. For example, Hospital C had more comorbidity than Hospital B (57.78% of Hospital C patients vs 15.00% of Hospital B patients were rated moderate or severe using a well tested index, p < 0.0001). After adjusting for patient mix differences, Hospital C scored significantly better on four of six outcome measures (i.e. angina, dyspnea, physical functioning, psychosocial functioning). For example, Hospital C's patients' mean scores on physical functioning at 8 week follow-up averaged 75.19 (on a 0-100 scale), while Hospital A's was 63.03 and Hospital B's was 48.57 (F-ratio = 4.95; p < 0.05). However, Hospital A scored significantly lower on all three resource intensity indicators (length of stay, ancillary charges, and total charges). For example, Hospital A's ancillary charges averaged $10,752 while Hospital B's and C's averaged $11,432 and $16,598 respectively. Between-hospital comparisons on adjusted mortality and satisfaction did not differ significantly. CONCLUSION: The "value" profiles (i.e. outcomes related to charges) produced by these three hospitals were substantially different. Studies that simultaneously measure outcomes, costs, patient mix and processes have potential to: (a) enable clinical teams to improve the measurable value of clinical care; and (b) enable purchasers to better evaluate which providers to select as preferred sources of care.

Acute Disease↗
PubMed1995

Toilet habits of children evaluated for urinary tract infection.

The toilet habits of 77 girls and 24 boys who were evaluated after having a urinary tract infection were examined prospectively. Children with known urological conditions that can predispose to urinary tract infections were excluded. A voiding cystourethrogram and renal ultrasound were performed, and a diary of toilet habits was obtained for all patients. Six children were lost to followup. Of the remaining 95 children imaging studies were negative in 60 (negative imaging group) and positive in 35 (positive imaging group). Only 10% of the negative imaging group were without constipation or abnormal voiding compared to 60% of the positive imaging group (p = 0.0001). Toilet habits can affect the development of urinary tract infections. Our data suggest that the evaluation of urinary tract infection should include an inquiry into these habits. Among children with negative imaging studies there may be functional problems that promote the development of urinary tract infections.

Adolescent↗
PubMed1995

Patient and visit characteristics related to physicians' participatory decision-making style. Results from the Medical Outcomes Study.

This article identifies the characteristics of patients and office visits associated with decreased mutual decision-making between physicians and patients. In the baseline cross-sectional survey of the Medical Outcomes Study we measured specific patient characteristics hypothesized to influence participatory decision-making (PDM) styles of physicians. We related these characteristics to the PDM style scores for their physicians. The study was conducted in solo practices, multi-specialty groups, and health maintenance organizations in Boston, Chicago, and Los Angeles. Over a 9-day period in 1986, 8,316 patients were sampled from the practices of 344 participating Medical Outcome Study physicians, representing general internal medicine, family practice, cardiology and endocrinology. Physicians' PDM style was measured using a 3-item scale included on the baseline questionnaire completed by patients after office visits to their Medical Outcome Study physicians. We found that the elderly (age 75 and older) and young adult (younger than age 30) patients, patients with high school education or less, minority patients, and male patients had the least participatory visits with their physicians. We also found that male patients seeing male physicians had the least participatory visits compared with male patients seeing female physicians, and compared with female patients seeing physicians of either gender. Our data indicated that PDM style increased as duration or tenure of the physician-patient relationship increased. Participatory decision-making style also increased with increasing length of office visits. The role of effective interpersonal care in optimizing patients' health outcomes may be underappreciated. We have identified seven patient and visit characteristics that maximize or compromise the effectiveness of interpersonal care. Recognizing those at risk for suboptimal interpersonal care may be a first step in improving the management of chronic disease. Key words: participatory decision-making style; interpersonal care; doctor-patient communication.

Adult↗
PubMed1995

Variations in resource utilization among medical specialties and systems of care.

As sweeping changes in the organization and delivery of health care are implemented, it is important to examine the relationship between various types of cost-containment efforts, health care costs, and quality of care. This article reviews the evidence that physician specialty training, the organization of physicians, and the method of physician payment are significant influences upon the utilization of health care services. Data from before the late 1980s raised the possibility that family practitioners employed fewer resources than general internists and that health maintenance organizations used fewer resources than solo practitioners. However, the studies from which these data were derived were marred by insufficient attention to patient mix, failure to account for interactions between specialty and system, and inadequate regard for the complexities of modern practice structures. More recent data from the Medical Outcomes Study (MOS) overcomes some but not all of these problems. In general, it can be safely concluded that primary care specialty training, group practice, and prepaid care are associated with less utilization. Nevertheless, much more research is needed to address remaining methodological problems and to obtain data that are generalizable to the wide array of modern practice settings.

Delivery of Health Care↗
PubMed1995

A comparison of various methods of collecting self-reported health outcomes data among low-income and minority patients.

In a randomized trial of different data collection methods, we challenged the untested assumption that reliable data cannot be obtained from lower-income and/or minority patients by self-administered questionnaires. We tested three methods of data collection among a sample of lower-income and minority patients (n = 697) in Indianapolis at a site for the Type II Diabetes Patient Outcomes Research Team. The study included a questionnaire literacy screening instrument to assess patients' functional literacy. Based on their functional literacy, patients were randomized to one of three methods of data collection: mail-out/mail-back, hand-out/assisted, or the in-home interview. We constructed a tiered system for reassigning nonresponders to alternative methods of data collection, using the in-home interview as the fall-back strategy. We compared the response rates, item completion rates, and internal consistency reliabilities of self-reported health status measures between patients with and without literacy limitations and across the three methods of data collection. Patients with and without literacy limitations, across methods of data collection, provided high-quality data, as evidenced by high item completion rates (> 84%) and high reliability assessments (internal consistency reliability coefficients > .80) for each health status measure. As part of the tiered study design, nonresponders randomized to either the mail-out/mail-back or the hand-out/assisted method were interviewed. These patients were significantly older, had significantly lower education and income levels, and had significantly poorer self-reported visual function as compared with those who responded to the originally assigned method. We conclude that expensive, labor-intensive data collection methods, such as in-home interviews, are not necessary for many low-income, minority patients to generate high-quality, reliable health status data. Using appropriate screening instruments, those patient subgroups needing special help can be screening instruments, those patient subgroups needing special help can be identified and targeted for more expensive data collection methods. This tiered approach has policy implications for the cost, feasibility, and quality of data collection in health outcomes research.

Aged↗
PubMed1995

Development and testing of a new measure of case mix for use in office practice.

Case mix has been shown to be of critical importance in studies of effectiveness and quality of care using health outcomes. How these variables are defined, combined, and used to adjust or increase precision in tests for differences in health outcomes has been a source of controversy. Because existing measures were developed to adjust mortality and have marginal relevance for the adjustment of functional status outcomes, especially in ambulatory settings, the authors developed a measure of case (or patient) mix that is specifically designed to adjust functional status outcomes measured in office practice or out-of-hospital settings. This measure, developed as part of Type II Diabetes Patient Outcomes Research Team project, uses patients' reports of symptoms and conditions, as well as patients' ratings of symptom intensity to characterize total disease burden. It differs from other measures of case mix in lack of dependence on diagnoses. Separate measures were developed for each of 15 different disease categories (e.g., chronic lung disease) grouped by body system affected. Within each measure, questionnaire items were combined to rate the severity of that disease on a 1 to 4 scale, according to definitions provided by clinicians. A single, global measure was developed by aggregating the 15 measures, weighted according to the expected impact of each disease category on functional outcomes and disability. In a sample of 1,738 patients, significant relationships were observed between the global case mix measure and functional status, disability days, and service utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

The impact of patient adherence on health outcomes for patients with chronic disease in the Medical Outcomes Study.

The association between adherence to medical recommendations and health outcomes (physical, role, and social functioning, energy/fatigue, pain, emotional well-being, general health perceptions, diastolic blood pressure, and glycohemoglobin) was examined in a 4-year longitudinal, observational study of 2125 adult patients with chronic medical conditions (hypertension, diabetes, recent myocardial infarction, congestive heart failure) and/or depression. Change score models were evaluated, controlling for disease and comorbidity. Patient adherence was associated minimally with improvement in health outcomes in this study. Only 11 of 132 comparisons showed statistically significant positive effects of adherence on health outcomes. We conclude that the relationship between adherence and health outcomes is much more complex than has often been assumed.

Adult↗